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Mobility of chromium and nickel in naturally contaminated soils
Kvapil, Jindřich ; Ettler, Vojtěch (advisor) ; Vaněk, Aleš (referee)
Soils developed on ultramafic rocks are relatively rich in trace elements, e.g. Cr, Co and Ni. Soils studied here and developed on serpentinites in the southern Bohemia exhibit high concentrations of these elements with up to several thousands mg/kg. Particularly soils with high Ni concentrations host specific vegetation and are are poor in nutrients. In this thesis we sampled two soil profiles located in the vicinity of closed Ni mining near Křemže in the southern Bohemia. Analyses of physicochemical parameters of soils, total concentrations of elements and their extractability using EDTA targeting "bioavailable" fraction were carried out. Concentrations of studied elements were the following: 27,1 - 423 mg Co/kg, 90,3 - 1190 mg Cr/kg, 170 - 4950 mg Ni/kg. Concentrations of Ni, Co and Cr significantly correlated with Fe (R2= 0.76-0.99) and were higher for agricultural soil profile with an increase as a function of depth. Maximum "bioavailable" concentrations were 47.6 mg Co/kg, 2.95 mg Cr/kg and 163 mg Ni/kg. Powered by TCPDF (www.tcpdf.org)
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Colloids in landfill waters and leachates
Janko, Jiří ; Ettler, Vojtěch (advisor) ; Matura, Marek (referee)
Contamination of surface water or groundwater by metals and/or metalloids, originating from landfill leachates is environmental concern in the vicinity of landfills designed for disposal for municipal solid waste (MSW). It is known that many organic compounds and metals/metalloids can be associated with colloids of the size 1 nm-1 μm. This relationship is mainly caused by the total surface area of colloids and consequently their binding capacity for contaminants occuring in the aqueous environment. In order to identify these associations in landfill leachates a cascade frontal filtration/ultra filtration is often adopted. Colloids obtained by this size-fractionation can be further studied by scanning electron microscope (SEM) or transmission electron microscope (TEM) coupled to energy dispersive spectroscopy (EDS). Typical example is a Vejen landfill in Denmark, which has been extensively studied, where leachate samples exhibited significant proportion of total metal content to be associated to colloids - Cd: 38-45%, Ni: 27-56%, Zn: 24-45%, Cu: 86-95% a Pb: 96-99%. Whereas Cd, Zn and Ni were mostly associated with smaller colloids (1-10 nm), other metals like Pb and Cu were bound to colloids of the size > 10 nm. A number of investigations from other landfill sites indicated similar results. Powered by TCPDF...
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Contaminant binding to colloids in water from a mining/smelting area
Walter, Dominik ; Ettler, Vojtěch (advisor) ; Faimon, Jiří (referee)
This study deals with the association of trace elements with colloids and particles in surface waters and groundwaters of mining and smelting district of Příbram. Colloids were studied using combination of cascade filtration a tangential flow ultrafiltration method to separate individual colloid fractions. Colloids were separated by filtration membranes with nominal pore size 0,8 μm, 0,45 μm, 0,1 μm, 100 kDa, and 5 kDa. Water samples were analyzed using ICP-OES, ICP-MS and HPLC. The data were used for thermodynamic modeling using PHREEQC-2 programme. The results show that major and trace elements can be divided into several groups, based on their abundance in individual size fractions. Most elements dominate in fraction of truly dissolved matter as dissociated ions (< 5 kDa), maximum concentration in colloid fraction is 5-20 % and almost exclusively in fraction 5 kDa - 100 kDa. Gradual decrease of concentration in all fractions at low ionic strength (1,2 mmol/l) was observed in case of elements such as As, Co, Cr, Si, Sb and U. Gradual decrease of concentration in several samples was observed for Cd, Fe, Pb, Mn and Zn. Dominant binding to colloids and particles in surface waters was observed for Fe and Pb, where these fractions accounted for over 90 %. The main factor influencing colloid...
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Stability of amorphous Mn oxide-based sorbent as a function of pH
Tomášová, Zdeňka ; Ettler, Vojtěch (advisor) ; Vítková, Martina (referee)
Soil systems contaminated by toxic metals and metalloids from anthropogenic sources present hazard for human health and other environmental compartments. Chemical stabilization using the Fe, Al and Mn oxides is one of the potential decontamination techniques. Manganese oxides exhibit a number of properties for being efficient sorbents of toxic metals, such as low point of zero charge, structure that allows ion acceptance and large specific surface. The focus of this thesis is to determine the stability of novel synthetic amorphous manganese oxide (AMO) as a function of pH using the pH-static leaching test. Manganese was released into the solution, with decreasing concentration in leachate as a function of pH: Mn concentration at pH 3 was 34 100 mg/L and at pH 8 only 90 mg/L. The data show that the solid phase mass loss is clearly dependent on the pH value, with the mass loss of 98,4 % and 11,2 % at pH 3 and 8, respectively. On the AMO surfaces, the newly formed crystals of rodochrosite (MnCO3) were observed; they partly control the Mn release at pH > 5. Based on the observed pH-dependent stability, it appears that the use of AMO as a sorbent of toxic metals could be a suitable method for neutral or alkaline soils, while its application for acidic soils seems to be unsuitable. Powered by TCPDF (www.tcpdf.org)
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Stability and efficiency of a new Mn-oxide based sorbent in contrasting soils
Knytl, Vladislav ; Ettler, Vojtěch (advisor) ; Komárek, Michal (referee)
Metal contamination of soils is one of the most important environmental problems throughout the world. One of the possible remediation technique of contaminated soils is based on chemical stabilization using various amendments. Due to their structure and sorption properties (pHZPC, specific surface, CEC etc.), Fe, Mn and Al oxides are suitable for this remediation technique. The focus of this diploma thesis is to evaluate the stability and the effectivity of the new synthetic amorphous Mn oxide (AOM) in soil samples with contrasting physicochemical parameters, mainly pH: soil N (pH 4,2), soil H (pH 5,4), soil S (pH 7,3). In a 90-day laboratory pot experiment with incubation of AMO in these soils we found that stability of AOM is strictly pH-dependent. Higher dissolution was observed in the most acidic soil N (mass loss up to 18%), whereas in alkaline soil S themass loss attained only 10%. The dissolution of AOM in acidic soils (N, H) was connected with a significant release of Mn into the soil pore water. For soils H and S the massive formation of secondary carbonate phases (rodochrozite - MnCO3, kutnahorite - (Ca,Mn)CO3) was detected on the AOM surfaces by X-ray diffraction analysis (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Granulometric measurements...
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Solid speciation of metals in tropical soils highly polluted by copper metallurgy
Kovářová, Lucie ; Ettler, Vojtěch (advisor) ; Vítková, Martina (referee)
Six soil samples corresponding to selected horizons (both topsoil and subsurface layers) from the forested and unforested soil profiles located in the vicinity of Mufulira Cu-Co smelter in the Copperbelt Province (Zambia) were investigated, in order to describe binding of main metal contaminants (Cu, Co, Pb, Zn) to soil constituents with a special emphasis on solid phase speciation. Sequential extraction procedure (SEP), X-ray diffraction (XRD) and scanning electron microscopy coupled to energy dispersion spectrometry (SEM/EDS) were used in this study. The highest bulk concentrations were found in soil samples from grassland areas located 3.6 and 8 kilometers from the smelter (Cu: 12 600 mg/kg, Co: 42.4 mg/kg, Pb: 40.6 mg/kg, Zn: 65.2 mg/kg). Copper was found to be the most mobile contaminant, also present in elevated concentrations in the subsurface soil layers of highly contaminated profiles, with substantial amount bound in the exchangable chemical fraction (19.3-25 mg/kg, 21-30 % of bulk Cu concentration). Besides the presence of lithogenic minerals, anthropogenic phases originating from mining and smelting activities were also observed in the heavy mineral soil fraction. These anthropogenic particles enriched in Cu or Co were identified by SEM/EDS as Cu-(Fe) oxides or sulphides of variable...
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Occurrence and speciation of metalloids in landfill leachates
Cihlová, Markéta ; Ettler, Vojtěch (advisor) ; Drahota, Petr (referee)
Landfillingiscurrentlythe prevailingwayof municipal solidwaste (MSW) disposal inmostcountries. Numerousprocessesinteractinginlandfills,are responsible forthe productionof landfillleachate. Apart frommanyotherpollutantsthe leachate containsmetalloids,especiallyarsenicandantimony. These elements,dependingonthe propertiesof landfills,canexistindifferentchemical species.The knowledge of theirspeciationisveryimportant,because itcanstronglyeffectthe toxicity,mobility and otherpropertiesof these elements.High-performance liquidchromatography(HPLC) andmass spectrometrywithinductivelycoupledplasma(ICPMS) hasbeenappliedtodeterminationof the speciationof metalloidsinlandfill leachates.The total concentrationof metalloidsanddistributionof theirspeciesare highlyvariable.Ithasbeenobservedthata certainfractionof metalloidsinlandfill leachatescanbe boundtocolloids,whichthusaffectthe mobilityandreactivityof these elementsin landfill environments.Knowledgeof the metalloidsspeciationenablestoassesstheirimpactonthe environmentandtosuggestappropriate technologyforpossible decontaminationof landfill leachates.
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Usage and environmental stability of MSWI bottom ash in road construction
Pospíšilová, Eliška ; Ettler, Vojtěch (advisor) ; Šebek, Ondřej (referee)
This bachelor thesis is a compilation of scientific and technical literature focused on treatments of municipal solid waste incinerator (MSWI) bottom ash such as carbonation or electro-kinetic remediation for the purpose of the decrease of the contaminant lechability. The carbonation the cheapest solution and is generally used as a first stage of MSWI bottom ash treatment. The second part of the thesis deals with possible applications of MSWI bottom ash for the construction purposes. Addition of bottom ash to the concrete is used as the alternative of natural purposes. Addition of bottom ash to the concrete is used as the alternative of natural gravel. Due to similar physical properties with crushed aggregate, bottom ash is also commonly used as a subbase of roads or pavement in numerous countries. Mixed bottom ash with the Portland cement can also find some applications as a light concrete with similar physical and mechanical properties.
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Mobility of trace elements in tropical soils
Kindlová, Helena ; Ettler, Vojtěch (advisor) ; Vaněk, Aleš (referee)
This bachelor thesis is focused on mobility of trace elements in highly weathered tropical soils. In the first part of the thesis, the taxonomy and classification of tropical soils, processes of their formation and occurrence throughout the world are explained. Basic properties of tropical soils with emphasis on the trace element mobility are mentioned in the second part. The final part of the thesis is dedicated to the potential sources of trace elements in tropical areas, their forms and speciations, and in particular binding to individual soil constituents.
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